Joined: Aug 2010
Posts: 12,727
Likes: 2,105
From: Madison, WI
Bikes: 1961 Ideor, 1966 Perfekt 3 Speed AB Hub, 1994 Bridgestone MB-6, 2006 Airnimal Joey, 2009 Thorn Sherpa, 2013 Thorn Nomad MkII, 2015 VO Pass Hunter, 2017 Lynskey Backroad, 2017 Raleigh Gran Prix, 1980s Bianchi Mixte on a trainer. Others are now gone.
Every cadence sensor or sensor for a wheel magnet that I have used was zip tied to the bike. USB rechargeable would suggest adding a quick release bracket to remove it and put it back in the same exact place later. Yeah, it is possible, but it adds complications.
It is rare when I need to replace a battery in a cadence or wheel sensor more than once in a season, a few times I have had to do it twice in a season but that was rare.
If the OP that posted this six years ago still has a problem, maybe try to find an old wired computer, I found the batteries in wired ones to last much longer than wireless. I often get a few years in a wired one.